Improve audio latency and pause handling

[ghost]

• Default ALSA latency target now uses the guest-requested buffer unless ANDROID_ALSA_LATENCY_MS is set.
• PulseAudio latency, fragment sizing, and AAudio performance patching are only applied when explicitly configured.
• PulseAudio remains running across activity lifecycle changes while AAudioSink is suspended and resumed through a PulseAudio CLI socket.
• Environment components now receive pause and resume lifecycle callbacks in dependency-aware order.
• Removed obsolete WINNATIVE_ALSA_* env-var UI entries after switching ALSA parsing to ANDROID_ALSA_*.